1. Field of the Invention
The present invention relates to a white hardening resin composition, a hardened material, a printed-wiring board including the hardened material, and a reflection board for light emitting devices including the hardened material.
2. Discussion of the Background
In printed-wiring boards, there have been recently increased applications of use that LED emitting by a low electric power in a backlight of liquid crystal display for mobile terminals, personal computers and televisions and the like, or a light source of lighting equipment is directly mounted. See, for example, the paragraphs [0002] to [0007] of Japanese Unexamined Patent Publication No. 2007-249148. The contents of Japanese Unexamined Patent Publication No. 2007-249148 are incorporated herein by reference in their entirety.
In this case, regarding an insulation film coated and formed as a protective film in a printed-wiring board, in addition to characteristics such as solvent resistance, hardness, solder resistance and electrical insulating properties generally required in a solder resist film, an excellent light reflectivity capable of utilizing emission of LED effectively has been desired.
However, a white solder resist composition conventionally used has had a problem that oxidation of resin due to light and heat irradiated by LED proceeds to turn yellow, lowering reflectivity with time.